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TR4/4A Motive power bleeder - TR4A master cylinder?

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Zimmycobra

Zimmycobra

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Folks:

I have just completed the mechanical restoration of my '65 TR4A IRS. The final job was the rear suspensions and brakes. Only thing left to do is bleed the brakes and clutch. As I am a one man shop (meaning my wife doesn't help too often), I try to use tools that do not need assistance. Several years ago, I bought a Motive Power Bleeder for my other toy (a 427 Cobra S/C Replica). It works wonderfully!! Can't say enough positives about the product or the company. Both are fantastic!!

Here is the problem. I checked with the guys at Moss Motors to determine the size of the reservoir, so that I could order the proper cap adapter from Motive for the brake bleed (I was at work so I couldn't measure it on the car.) I was told 2.5", which did match to one of the adapters from Motive. Sadly - when I went to use it today, it is slightly too big (horrible disappointment! I was hoping to do a test drive today - first time the car would have driven in 30 years!)

When I measured the master cylinder neck, I get about 2.45". Can someone verify that I am correct? Because I do not see this as a standard adapter from Motive and that surprises me. Has anyone used Motive's Power Bleeder on their TR4A master cylinder and if so what adapter did you use? I am so confused!!!!!!!!!!!!

As usual - thanks to all for your sage and helpful advice.
 
Motive also has a universal top that clamps over the reservoir hole. I have a motive bleader. but haven't bled my 4A yet. For the TR6, I used an old MC cap, and attached an air hose nipple to it and it worked OK.
 
Thanks, Peter. I may have to make my own also. I prefer to get a factory one when possible as they tend to be better suited, but in this case I am not sure. I need a new cap anyway, so Maybe I'll order the new cap and make an adapter out of the old one.
 
Okay: new info from Motive Products. My original master cylinders still have the formed metal caps for the Girlings. The Motive caps that are on their adapters are plastic and work with the Girling units that have the plastic caps. While the designation for the master cylinders is still a 2.5" reservoir diameter, the newer ones with the plastic caps have bigger thread on the outside of the reservoir making the actual cap bigger in diameter. The plastic caps will not fit on the metal cap reservoirs.

The solution is to use Motive's Universal Adapter for round reservoirs. Mine is on its way and hopefully will get to me in time to work this weekend and finally see if the brakes (therefore - the car) will work. Keep your fingers crossed for me, please. It has been 4 years in the making.
 
They push fluid faster than you think so don't forget to keep fluid in there.
 
Thanks, Peter. I have used the bleeder before on my other toy car (427 Cobra S/C replica) and I do remember that. It is one of the reasons that I like them so much. Really gets clean fluid in and air out.
 
A word of caution, which I doubt you need. If you are making your own cap (which I think you decided against) you need to make sure the nipple you install in the cap is well sealed. I made my own cap for the clutch master cylinder on my 4A and I did not do a good job making sure the nipple had a good seal against the cap. Long story short - I spilled brake fluid everywhere. My only saving grace was that I had POR-15 on the bulkhead and battery tray and POR-15 is nearly impervious to brake fluid. I have been using my Motive on modern cars for years without any troubles, and I should have known better.
 
Ian:

Funny you should post that comment. I spoke to Eric (President of Motive Products) on Monday and he mentioned a similar story of caution to me. It seems that drilling a hole in the old, original metal Girling cap is a real problem. As he explained, the cap is made from formed tin. In typical style of that era, it is actually two thin layers of tin that were formed with an aluminum disk in between to give it some rigidity and strength. Well, as you drill the hole, it will easily go through the top layer of tin. When it starts to go through the aluminum disk which is free to rotate, it grabs on the drill bit and spins very fast destroying the cap. It may be possible to get it to work if you are very careful and lucky, but I doubt that it would work for me.

My universal cap from Motive should arrive this Friday or Saturday and I should be able to get everything finally bled and finished. I'll update this thread after the event. Thanks.
 
Just wanted to let everyone know that I was able to use the Motive Bleeder to get the clutch and brakes bled last weekend. Everything went well and I was able to take the car down my driveway (about 1,000 feet) and back without a problem! It starts, engages, steers, shifts, and stops well and easily. I was very gratified. First time in the 4 years I've been restoring and about 25 years since last driven before. Still a lot of cosmetic things to do (paint - interior- trim - top), but the mechanicals are basically finished. Feels great.

If you are interested: https://youtu.be/UqWAx4LXD3k. Thanks for everyone's help.
 
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